1. Field of the Invention
The present invention is based on a door system to move and lock at least two door leaves, which door system may be equipped with a drive device to move the leaves between a position that opens a passage and a position that closes the passage, as well as with a locking device. The locking device can have a motor-side drive unit which is attached to a door frame profile, and top and bottom locking elements, whereby the top locking elements can be actuated by the drive unit in the position of the leaves that closes the passage, and to create a substantially interlocking or form-fitting connection in the vicinity of the top of the leaves between the leaves and a stationary part of the doors, whereby there can be lower locking elements that can be actuated by the drive unit and are located in the vicinity of the bottom of the leaves to create an additional interlocking connection between the leaves and the stationary part of the door system, and whereby the drive unit can be effectively connected with the locking elements only when the leaves are closed for locking and unlocking.
2. Background Information
A similar locking device is described in European Patent No. 0685621 A1. The locking device has top and bottom locking elements on leaves of an automatically actuatable door system which, when the leaves are in the closed position, lock the top and bottom portions of the door leaves. The top and bottom locking elements are mechanically coupled by means of a rod, so that both locking elements are actuated when the drive unit is started by means of a pivoted lever. The top locking elements lock the neighboring leaves with respect to one another, while the bottom locking elements fix the respective leaf directly to the floor. The top and bottom locking elements are automatically moved into an interlocking connection by a single drive unit. The interlocking connection of the locking elements thereby acts in all directions, i.e., both in the direction of movement and also perpendicular to it. The door system can be operated fully automatically by means of a switch. The door system can be locked and unlocked manually in the event of the failure of the power supply system.
The type of conversion of the motor movement to the locking elements and their complex mechanical coupling system must be seen as a disadvantage, because complex and time-consuming adjustment measures on the entire system are necessary during the installation and as a result of the inevitable tolerances that occur during the operation of the door system. On account of the direct mechanical coupling of the locking elements, it may not be possible to compensate for differences in the distances traveled between the top and bottom locking element, e.g. differences that may be caused by dirt in the floor guide, which can lead to the failure of both locking mechanisms. The pivoted lever device that couples the locking element during the movement of the leaves also requires a high degree of precision of the movement process. Even minor deviations mean that the driver pin, provided for the purpose, on the pivoted lever does not come into engagement with the corresponding indentation of a locking bracket, because the plane of the indentation is perpendicular to the direction of movement, and the indentation in the direction of movement of the leaf must be guided by means of the driver pin.
An additional disadvantage of at least one locking device described in some publications is that the locking device of the leaves can be tampered with mechanically--that is, a pin-shaped tool can be pushed between the leaves, so that when the appropriate pressure is exerted against the locking bracket, the top and bottom locking elements can be moved from their position and the leaves can be displaced.